Is there a RAID 7?

He could be getting confused in that there are 7 "levels" of RAID, but they are RAID 0 through RAID 6.

There is however a non-standard RAID 7, but it isn't a industry standard like the main levels. You can read up a bit on it here: http://www.pcguide.com/ref/hdd/perf/raid/levels/singleLevel7-c.html

There are a number of non-standard RAID levels, if you're interested you can read more on Wikipedia: http://en.wikipedia.org/wiki/Non-standard_RAID_levels

Raid 7 is a trademarked marketing term used by the Storage Computer Corporation. The controller card uses its own CPU and combines striping and RAID-5-like storage.

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